Revert "Set default extensions for most save files"

This reverts commit 6f21bacd82.

qrenderdoc/Windows/Dialogs/TextureSaveDialog.cpp

@@ -526,8 +526,8 @@ void TextureSaveDialog::on_browse_clicked()
 
   QString *selectedFilter = NULL;
 
-  QString filename = RDDialog::getSaveFileName(this, tr("Save Texture As"), QString(), filter,
-                                               QString(), selectedFilter);
+  QString filename =
+      RDDialog::getSaveFileName(this, tr("Save Texture As"), QString(), filter, selectedFilter);
 
   QFileInfo checkFile(filename);
   if(!filename.isEmpty())